/**
 *
 * The MIT License
 *
 * Copyright (c) 2008 the original author or authors.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:

 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

package com.googlecode.charts4j.parameters;

import java.util.List;

import com.googlecode.charts4j.Color;
import com.googlecode.charts4j.collect.ImmutableList;
import com.googlecode.charts4j.collect.Lists;

/**
 * Class for building chart colors parameter string for the Google Chart API.
 *
 * @author Julien Chastang (julien.c.chastang at gmail dot com)
 */
final class ColorsParameter implements Parameter {

    /** The Google Chart API colors parameter. */
    private static final String URL_PARAMETER_KEY = "chco";

    /** The colors. */
    private final List<List<Color>>   colors            = Lists.newLinkedList();

    /**
     * Add the colors. This is a 2D data structure because in some cases
     * (e.g. individually colored bars in a bar chart) there can be more
     * than one color in a data series. In most cases, however, the inner
     * list, is only going to be 1 long.
     *
     * @param colors
     *            the colors
     */
    void addColors(final ImmutableList<? extends ImmutableList<? extends Color>> colors) {
        for (ImmutableList<? extends Color> listOfColors : colors) {
            final List<Color> l = Lists.newLinkedList();
            l.addAll(listOfColors);
            this.colors.add(l);
        }
    }

    /**
     * {@inheritDoc}
     */
    public String toURLParameterString() {
        final StringBuilder sb = new StringBuilder(URL_PARAMETER_KEY + "=");
        int cnt = 0;
        for (List<Color> l : colors) {
            sb.append(cnt++ > 0 ? "," : "");
            int i = 0;
            for (Color color : l) {
                sb.append(i++ > 0 ? "|" : "").append(color);
            }
        }
        return !colors.isEmpty() ? sb.toString() : "";
    }
}
